1. Field of the Invention
The present invention relates to a source delivery surgical staple device for delivery of a source/seed directly to a surgical staple margin; and more particularly, to a source/seed delivery surgical staple device that provides for the direct delivery of sources or seeds containing radiation, and/or other tumor fighting means such as chemotherapy, in conjunction with surgical staples, whereby direct delivery of the seeds during surgery to the staple margin applies brachytherapy (local radiation source) to the staple margin in a controlled consistent manner.
2. Description of the Prior Art
Radiotherapy (radiation oncology, or XRT) is the medical use of ionizing radiation as part of cancer treatment to control malignant cells. Radiotherapy may be used for curative, adjuvant or palliative treatment. Total body irradiation (TBI) is a radiotherapy technique used to prepare the body to receive a bone marrow transplant. Radiotherapy has several applications in non-malignant conditions, such as the treatment of trigeminal neuralgia, severe thyroid eye disease, pterygium, pigmented villonodular synovitis, prevention of keloid scar growth, and prevention of heterotopic ossification. The use of radiotherapy in non-malignant conditions is limited partly by worries about the risk of radiation-induced cancers. Radiotherapy is commonly combined with surgery, chemotherapy, hormone therapy, Immunotherapy or mixtures thereof. Most common cancer types can be treated with radiotherapy in some way.
Brachytherapy, also known as internal radiotherapy, sealed source radiotherapy, curietherapy or endocurietherapy, is a form of radiotherapy where a radiation source is placed inside or next to an area requiring treatment. Brachytherapy is commonly used as an effective treatment for cervical, prostate, breast, skin and lung cancer and can also be used to treat tumors in many other body sites. Brachytherapy can be used alone or in combination with other therapies such as surgery, External Beam Radiotherapy (EBRT) and chemotherapy. Various methods of brachytherapy have been employed, including use of a vicryl patch/mesh construct having brachy therapy seeds sewn therein and applied over a staple line, or through utilizing radioactive surgical staples
When a patient is deemed physiologically healthy, the operation of choice for lung cancer has been pneumonectomy, taking the entire lung out, or lobectomy, taking an anatomic unit along with its vascular supply and lymphatic drainage out. Instead of a pneumonectomy or lobectomy procedure, the physician may choose to perform a wedge resection. Wedge resectioning involves the removal of a triangle-shaped slice of tissue massing the tumor or some other type of tissue that requires removal, followed by surgical suturing via staple line or resection line. In general, repair of the wedge resection is simple by way of the staple/resection line and allows the underlying organ to retain its shape without distortion. Typically, the wedge resection leaves just a single stitch line. Despite the advantages concerning the operation procedure, wedge resections have not been considered an acceptable oncological resection method for cancer in patients who are fit physiologically to undergo lobectomies. What makes a wedge resection undesirable in cancer patients is the rate of recurrence of cancer at the staple line or resection line.
One method of brachy therapy involves implementation of a vicryl patch/mesh construct wherein brachy therapy seeds are sewn into the patch and applied on the line of the staples that the wedge resection was taken from. Generally mesh is provided with radioactive seeds through the intercostal access site. The width of the mesh is typically chosen based on at least 2-cm coverage of the lung parenchyma on each side of the staple line. 125I pellets incorporated within absorbable polyglycolate suture are typically woven into the customized mesh at 1-cm intervals. Landreneau et al., “Intraoperative Brachytherapy Following Thoracoscopic Wedge Resection of State 1 Lung Cancer”, Chest Off. Pub. Of the Am. Coll. Of Chest Phys. Treatment is generally randomized to wedge resection alone versus wedge resection+brachy therapy using vicryl patch. It has been found that the wedge+brachy therapy yields a 1% local recurrence (LR), while wedge alone resulted in a 19% LR. However, despite the finding of positive results tending to the brachy therapy mesh+wedge resection treatment combinations, the procedure poses disadvantageous using the mesh. First, it's very operator dependent. Second, reproducibility is tedious, especially in video assisted cases.
Another method of brachy therapy proposes the uses of surgical staples having radioactive material sealed within a titanium tube to serve as legs of a tissue fastening system. Radioactive sources are appointed to be secured in position directly adjacent to the surgical resection. Dose distribution is precisely planned prior to the surgery to achieve the desired result. The delivery system is designed to be used in conjunction with the commercially available surgical stapling instruments widely used for VATS. The delivery system is constructed as a sidecar attachment that is adapted to attach onto a commercially available surgical stapler. The sidecar device contains the sources (with fastening legs)/radioactive staples in predetermined positions. After deployment of the surgical staples to excise the pulmonary wedge, the sidecar is independently activated to deploy the sources immediately adjacent to the surgical staples. “Brachytherapy Delivery System for Treatment of Lung Cancer”, Source Production & Equipment Co., Inc., UMass, Mass. Med. Device Development Center, pp 1. Unfortunately, the armed staple and delivery system therein involving the sidecar on the commercial surgical staple results in a one-to-one relationship between the “sources”/radioactive staples and the number of surgical staples required for a given operation.
Disadvantages attending to heretofore disclosed methods and systems for delivery of brachy seeds include 1) difficulty in precise placement of the brachytherapy seeds/sources relative to the surgical margin, 2) separate surgical procedures for implantation of the brachytherapy weeks after surgery, and 3) exposure of radiation dose during implantation. Normally after a lobectomy patients have to wait between six to eight weeks to recover from surgery before the radiation treatment can begin. Most oncologists don't start treatment of any form until three months from the time of the lobectomy surgery. As a result, the patient is not immediately treated with the radiation and therefore risk of recurrence of the tumor increases.
There remains a need in the art for a source delivery stapler device that allows for precise delivery of radiation therapy to the surgical margin, while also providing a single step operation that allows the implantation of the radiation during a surgical re-sectioning procedure.